This is the PC-E NIKKOR 24mm f/3.5D ED lens, which was announced on January 29, 2008:
Download the Nikon 24mm f/3.5D PC-E Manual (PDF link).
Sample photos
An official, full-resolution sample photo taken with a Nikon D600.
Standard and optional accessories and add-ons
The filter thread size on the 24mm PC-E is 77mm, which means you’ll want to be looking at purchasing 77mm filters.
The following are standard accessories supplied in-the-box:
- 77 mm snap-on front lens cap LC-77
- Rear lens cap LF-1
- Bayonet hood HB-41
- Flexible lens pouch CL-1120
Optional accessories:
- Nikon-made 77mm screw-in filters: 77mm Circular Polarizer II, 77mm Soft Focus Filter and 77mm Filter NC (Neutral Color).
The full list of compatible accessories is available at Nikon USA and in the lens manual.
Resources
Official Nikon 24mm f/3.5D PC-E websites:
Nikon 24mm PC-E press release on DPReview.
Related
Nikon Lenses — Main page.